Program Mode
The OUTPUT Page
6-39
Minimum Rate
This is the slowest rate at which the LFO runs. When its Rate Control is set to
OFF
, or when the
control source assigned to it is at its minimum, the LFO runs at its minimum rate. As previously
mentioned, the values 1/4 note, 1/8 note, 1/8 triplet, and 1/16 note sync the Minimum Rate with
the PC3A’s system tempo. Of course, if you choose to tempo sync your LFO, then the LFO rate is
fixed, and you can specify neither Maximum Rate nor Rate Control. The display changes thusly:
Maximum Rate
This is the fastest possible rate for the LFO. When its Rate Control is set to
ON
, or when the
control source assigned to it is at its maximum, the LFO runs at its maximum rate.
Rate Control
Assign any control source in the list to modulate the LFO’s rate between its minimum and
maximum. A continuous control like the Mod Wheel is a natural choice, enabling you to get just
about any rate between minimum and maximum. But you can use a switch control too, to get just
the minimum or maximum with nothing in between. Assigning
MPress
(aftertouch) as the rate
control for an LFO vibrato gives you an easy way to increase the vibrato rate in realtime, as you
can on many acoustic instruments.
LFO Shape
The shape of the LFO waveform determines the nature of its effect on the signal its modulating.
An easy way to check the effects of the different LFO shapes is to set
LFO1
as the value for the
Src1 parameter on the PITCH page, and set the Depth for Src1 to
400 cents
or so. Then go to the
LFO page, set the Min and Max rates for LFO1 at
0.00 Hz
and
4.00 Hz
or so, and set the Rate
control to
MWheel
. Now play your MIDI controller and you’ll hear the LFO’s rate change when
you move its Mod Wheel. Select different LFO Shapes and check out the effect on the pitch.
LFO Phase
Use this parameter to determine the starting point of the LFO’s cycle. One complete cycle of the
LFO is 360 degrees. 0 degrees phase corresponds to a control signal value of 0, becoming positive.
Each 90-degree increment in the phase represents a quarter-cycle of the LFO.
When an LFO is local, the phase parameter gives you control over the starting point of the LFO
for each note (for example, you could make sure every vibrato started below the pitch you played
instead of at the pitch you played). The LFO’s phase also affects global LFOs, although it’s often
indistinguishable, since global LFOs start running as soon as the program containing them is
selected, even if you don’t play any notes.
